It depends as my stimming changes over time. I've settled back into the (annoying for others) habit of making a noise as I breathe in, I don't even know what it is that I do, but it's like a dull click in my head when I do it. Other things would be foot twitching, blinking a particular way, hair playing, beard scratching, finger rubbing, and so on. I used to do some clicky thing with my eyes but gladly stopped that as I wasn't sure it was very good for me.